I Need Help Determining Coal Boiler Size

josepapa1 · Post by **josepapa1** » Wed. Jul. 23, 2008 9:45 pm

I just had a fire in my home and the entire interior of the house has been gutted including the heating and air. With that said it is time to think COAL!! The house is 5500 sq ft which does not include the finished basement. It is a 3 story home plus basement. I also have an inground pool about 32,000 gallons which I would like to heat with the coal furnace. The house and the pool were heated with propane and it was sending me to the poor house. I live in lake Wallenpaupack PA. I was looking at either an outdoor sytem that burns coal "the Coleman" or get an interior unit and put it in my 3 car detached garage which is about 100 +/- ft from the house. I am extremly handy and would have no problem installing the unit with the proper diagrams. If I put it in the garage then I would pipe it underground thru the pex insulated systems that I have seen to the house where the plumber would make the connection to a back-up oil burning boiler. I want the coal unit to be my primary and the oil to be my back-up. We are heating the house with hot water baseboard and radiant heat and also making hot water with it. Based on what I am seeing with delays, I want to order this immediatly but I need the help for sizing and installation guidelines. I appreciate any and all help as soon as possible. Thanks in advance!! Joe 570-226-9022

beatle78 · Post by **beatle78** » Wed. Jul. 23, 2008 9:54 pm

Joe,

What's the BTU rating of you're current propane boiler?

I would think that would give you a good indication of the size coal boiler you need since all boilers are rated in BTUs. I know there is a different between BTU input rating multiplied by the efficiency of the appliance, but that raw input BTU rating should give you a good start. (I think most appliances are rated in BTU input and not BTU output.

The AA-260 comes to mind, but I'll let Greg way in on that one!

josepapa1 · Post by **josepapa1** » Wed. Jul. 23, 2008 10:10 pm

I think it was something like 360,000 but that only heated the house and I would like to incorporate the pool in to this also. I know when the pool is on the heat is off. I just want to get this right. We had the house perfect before the fire, now I get to get a second shot at it and I want to tweak it...

josepapa1 · Post by **josepapa1** » Wed. Jul. 23, 2008 10:19 pm

Based on all the research I have done, the Keystoker model with a big butt hopper is what I am looking for if I use an in-door unit. Any thoughts though to the outside units that are out there? Price comparison??? What is cheaper at the end? Which will last longer? Which is better??

Adamiscold · Post by **Adamiscold** » Thu. Jul. 24, 2008 7:55 am

360,000 BTU's is a lot. I would think and I am not an expert here but you might want to consider going with a couple of smaller systems in stead of one large one, that way you could turn off one section of the house if it's not being used and save money. The baseboard and the radiant tubing are going to be at two different temperature settings. You might want to look into investing into some type of solar heating to either heat or preheat the water, which should help on the stress of heating such a large house. Also maybe some solar heating for the pool which I am assuming is indoors? Any type of solar will return your investment in a short term. Because it's such a huge house and you are seemingly going to be making a huge investment you may even want to look into a geothermal system, being how large your place is they are more then likely going to recommend a couple of systems instead of one where by having just the one would be too large for cooling in the summer time.

Post by **Rob R.** » Thu. Jul. 24, 2008 8:26 am

How old is your home? Is it well insulated? 360,000 btus seems pretty high for 5500 sqft. If you have time, work through a heat loss calculation and let us know what you come up with. This calculator should give you a good estimate: http://www.alternateheatingsystems.com/btucalcula ... ulator.htm

I live in a 1960's era 3000 sqft home with average insulation and new windows (lots of windows), on the cold days my BTU requirements work out to approximately 40 btus per sq ft per hour. I practically live in Canada, so I'm sure the winters aren't as frigid in your area. Unless the wind blows through your house, I don't see why an AA-260 wouldn't meet your needs.

josepapa1 · Post by **josepapa1** » Thu. Jul. 24, 2008 8:54 am

The house is 2 X 6. All new anderson windows with low e glass will be installed and it will be well insulated. The Kitchen, family room has a 24ft cathedral ceiling but I have 3 fans keeping the heat down. The rest of the house is 8 ft ceilings. 1/2 blue board insulation on the entire outside with siding. The original house was built in 1985. Multiple systems is not where I really want to go so.

Yanche · Post by **Yanche** » Thu. Jul. 24, 2008 11:20 am

You need multiple boilers. One coal and one an alternate backup fuel. Size the coal boiler for providing the heat needed for all but the coldest days. Piping should be in a primary-secondary loop for automatic supplemental heat from the second boiler. Take your time and design the system right from the beginning. Buy this book.

http://www.hydronicpros.com/publications/index.php?id=24

It comes with software that will help you design your system. If you can't afford everything now at least do the basics of the heat distribution system right from the beginning. You need to do a heat loss calculation on your home. The beginning chapters in the book tell you how.

If your house will also be A/C you need a Manual J analysis. This will give you heat loss and heat gain. Best left to a professional. You want "full Manual J" 8th edition analysis. If the guy doing it doesn't have a computer to do the calculations find someone that does.

Underground insulated PEX piping will work just fine. You will need an anti-freeze loop to heat your pool with heat exchangers unless you design a winter drain down system. Do not oversize the boiler just because of the pool BTU load. Your heating season efficiency and economy will suffer. Again buy the book!

LsFarm · Post by **LsFarm** » Thu. Jul. 24, 2008 2:59 pm

A very well insulated and sealed 5000sqft house may not need even an AA260, an AA or AHS 130 may be enough,, or an EFM 520.. with baseboar heat, and some radiant floor heat [I did read that, right?] you won't have that great of a BTU load in a newly refurbed and insulated house.

The pool is not really an issue.. you usually won't heat the poot year-round.. you will start to heat it when the heating load on the house starts to decrease in April and May..

I'm heating 4100 sqft of poorly insulated old drafty farmhouse, 41 exterior windows, about half are OLD thermopane [1970's] the rest single pane.. AND I'm heating a 2400 sq fit shop with my AA 260 boiler.. on about 10-12 tons per heating season.

Greg L
..

josepapa1 · Post by **josepapa1** » Thu. Jul. 24, 2008 5:13 pm

Thanks for the info. I am using mostly radiant instead of baseboards. Based on the cost of the copper, the radiant is turning out to be less money and will heat the house better based on what I have read. Now the question is who to get the boiler from and what kind. I called someone today but never got a call back. I know there will be a wait and that is ok because I have about 6 months before I get back in the house. If you have any suggestions with local people in my neck of the woods to purchase a unit from please speak up. I am about 30 minutes south of Scranton PA.

Adamiscold · Post by **Adamiscold** » Thu. Jul. 24, 2008 5:24 pm

Jose, one of the best things about radiant floor heating is the temperature is around 120-130 compared to baseboard that is usually around 180. So you should save money on not having to heat the temperature so high.

beatle78 · Post by **beatle78** » Thu. Jul. 24, 2008 6:31 pm

jose,

I don't think anyone has explained this to you yet (or you may already know).

I would NOT get a hopper fed boiler if I was doing an outside installation. I would 100% get an auger fed unit and build a bin right inside whatever shed you are putting the boiler in.

If you are designing from scratch, you could design a system where you only have to tend to the coal once and twice a year.

You will still have to empty the ashes every coupld of days UNLESS you put an auger into the ash bin and have the ashes automatically taken out each day for you

josepapa1 · Post by **josepapa1** » Thu. Jul. 24, 2008 9:34 pm

I have read about auger set-up's but I seen where people seemed to be having issues with them. Can anyone direct me to any sites or info on auger set-ups. I am not worried about having to feed the hopper every couple of days. It will reming\d me to clean the ash but the auger set-up has merit

josepapa1 · Post by **josepapa1** » Thu. Jul. 24, 2008 9:43 pm

Beetle78,

I went on to AA"s site and saw exactly what your were talking about. I see you use that sytem. How do you like it? What kind of cost should I expect with a system like that. Do you know any local dealers to me in PA?
Thanks, Joe

mikeandgerry · Post by **mikeandgerry** » Fri. Jul. 25, 2008 2:55 am

Drive to AA in Williamsport to pick it up, 6800USD. Problem will be when you can get it. Yanche is right: dual system: Oil + coal. You will be waiting for AA coal boilers into the heating season.

http://www.hvaccomputer.com/index.asp is an ASHRAE Manual J online calculator that is available for one month for $49 for homeowners. (Pros can buy it for unlimited use for $389 ) It does both the loss for heating and gain for cooling. I found it to be spot on, easy to use and very detailed. For example, if you have one wall that is half concrete, half of that insulated, half of that uninsulated and the rest of the wall framed and insulated, it allows you the flexibilty to breakdown that wall to calculate those value exactly. It was the best $50 I spent on my project. I would never have followed manual j exactly without it.